This project is concerned with the development of the carbon-13 magnetic resonance technique for use in biological studies. It involves the development of the basic spectroscopic technique with emphasis on biological applications. Relaxation studies of carbon-13 multiplets are being developed to acquire the wealth of information on structure of molecules in the liquid state which was not acquired previously. In addition, details of molecular dynamics are readily obtained. Isotopic labeling of macro-biological molecules is underway to provide the biologically interesting systems requiring the spectroscopic techniques. BIBLIOGRAPHIC REFERENCES: Carbon-13 Magnetic Resonance Study of Structural and Dynamical Features in Carbamylated Insulins, J. J. Led, D. M. Grant, W. J. Horton, F. Sundby, and K. Vilhelmsen, J. Amer. Chem. Soc., 97, 5997 (1975). The Importance of Local Anisotropic Effects and Ring Current on Proton Shieldings in Aromatic Hydrocarbons, M. Barfield, D. M. Grant, and D. Ikenberry, J. Amer. Chem. Soc., 97, 6956 (1975).